For what it is worth, I pumped my pond dry due to the geography involved. I also had 3 field tiles draining into my pond as well as what I can best describe as a natural spring in one end. In my case, I had to keep a sump pump in place the entire time I excavated to keep the water out and allow me to work. A decent pump should handle that water without much trouble if you decide to go that route. I used a cheap 3/4 HP unit from harbor freight.
